//writedile.js
let fs=require('fs')
let f1,f2;
fs.readFile('./tect1.txt','utf8',(err,data)=>{
    f1=data
})
fs.readFile('./tect2.txt','utf8',(err,data)=>{
    f2=data
})
fs.writeFile('./myfile.txt',f1+f2,err=>{
    if(err){
        console.log(err);
    }else{
        console.log("写入成功！");
    }
})